Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/13/22

Area Forecast Discussion
National Weather Service Goodland KS
835 PM MST Sat Feb 12 2022 .SHORT TERM...(This evening through Monday) Issued at 256 PM MST Sat Feb 12 2022 At the start of the short term period, the latest RAP analysis shows the CWA having a north-northwesterly flow aloft as the CWA is underneath the back part of a trough with a ridge over the western CONUS. Current satellite imagery is showing some midlevel clouds north of the CWA that are moving in a south-southeast direction. By Saturday night, forecast guidance shows the ridge-trough pattern continuing aloft and progressing a bit eastward. At the surface, dry conditions are expected in the CWA with winds shifting to the northwest after midnight as a surface low travels southeast through central NE into eastern KS. Overnight lows for tonight look to be in the upper teens to the lower 20s. On Sunday, forecast models show the ridge moving eastward over the western half of the CONUS by the evening hours allowing for a northwesterly flow aloft throughout the day. At the surface, there looks to be a brief weak cold front associated with the aforementioned low passing quickly though the eastern part of the CWA. However, a surface trough moves in over eastern CO by the afternoon which looks to usher in a warmer air mass from the west-southwest. There may be some elevated fire weather concerns for areas along and west of KS-27 with a minimum RH values in the upper teens and wind gusts above 20 kts possible. Daytime highs on Sunday look to be in the middle 50s to the lower 60s with overnight low temperatures in the lower to upper 20s. For Monday, models show the flow being mostly westerly during the day with a brief transition to northwesterly when a brief trough passes through the flow in the evening. At the surface, dry conditions continue for the CWA with breezy southerly winds during the afternoon. Fire weather concerns look less likely for Monday at this time, but this will be monitored in case they change. Monday`s daytime highs look to be in the middle 50s while overnight lows in the lower to middle 20s can be expected. .LONG TERM...(Tuesday through Saturday) Issued at 156 PM MST Sat Feb 12 2022 Main focus for this part of the forecast will be the trough moving onto the Plains mid week. Starting out this period will be an upper level ridge over the forecast area. WAA on Tuesday will allow temperatures to be well above normal. Tuesday night a strong cold front will move through accompanying the upper level long wave trough. Behind the front northerly winds will increase, along with the CAA. Precipitation will also move in behind the front as the trough axis approaches. The track of the trough has changed very little over the last five model runs of the GFS. The latest model run has sped up the trough arrival from the prior four runs. The ECMWF has shifted the trough slightly further north over the last four runs. However the trough is still well south of the forecast area. Since the trough remains so far south, precipitation chances have gone down. Confidence is moderate for even an inch of snow to occur. Regarding precipitation type, confidence is low that there will be much rainfall before changing to snow due to the CAA Thursday. For temperatures, highs were raised above model consensus for Tuesday given the WAA. Highs for Wednesday and Thursday, along with lows for Wednesday night were lowered due to the continued CAA over the forecast area. Highs for Wednesday may not be cold enough. Wind chills for sunrise Thursday morning could be 5 to 10 below zero. Behind this upper level trough temperatures warm as the jet stream shifts east of the forecast area, allowing WAA to move in. && .AVIATION...(For the 06Z TAFS through 06Z Sunday night) Issued at 835 PM MST Sat Feb 12 2022 KGLD...VFR conditions are expected through the period. A west- northwest wind around 12kts is expected through 07z, decreasing back to speeds around 10kts from the west or northwest through 16z. From 17z-22z modest 3 hour pressure falls develop which will back winds to the southwest with gusts around 25kts or so. After 23z west to southwest winds subside to around 10kts. KMCK...VFR conditions are expected through the period. A west wind around 12kts is expected through 08z, veering slightly to the northwest and decreasing to around 10kts through 16z. After 17z modest 3 hour pressure falls develop which will cause winds to back to the southwest at speeds around 12-13kts with some gusts from 20z-22z. After 23z a west to southwest wind around 10kts is expected. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...076 LONG TERM...JTL AVIATION...99
Area Forecast Discussion
National Weather Service Grand Rapids MI
922 PM EST Sat Feb 12 2022 LATEST UPDATE... Update/Marine .UPDATE... Issued at 902 PM EST Sat Feb 12 2022 The snow showers have been tracking further inland than expected. Part of the reason for this is that the wind was out of the west northwest. Based on the 00z HRRR those snow showers tracking through Kent County may reach the Lansing region. Thus...we bumped up the POPs to account for an increased chance to see some snow showers for inland locations. One consideration was to add Ottawa County to the winter weather advisory with several high res models suggesting an increased potential for at least minor impacts in that county. However the SPC HREF mean 12/24 hr snowfall keeps the risk for heavier snow south and west of Holland. && .DISCUSSION...(This evening through next Saturday) Issued at 335 PM EST Sat Feb 12 2022 -Cold with Lake Effect into Monday Will extend the Winter Weather Advisory for Allegan and Van Buren Counties through 7 PM Sunday. Lake snows continue to hug the shoreline tonight due to enhanced sfc convergence along a N-S oriented sfc trough, and an upper low dropping southeast from the Arrowhead of MN gives snow showers another boost on Sunday. Additional localized 6" accums likely. Some uncertainty exists as to the exact behavior of wiggly N-S dominant snowband late tonight and early Sunday, with some HiRes guidance pushing it mostly offshore for awhile. Also some hints of a possible mesolow circulation developing near/south of Holland by 12Z Sunday which could produce some intense snow rates if it materializes. Either way, the snow showers do return by Noon Sunday and we could see some rather heavy bursts as the convective depth exceeds 10K ft while a strong mid level shortwave is moving through in the afternoon. Heavier cellular snow showers could even develop well inland from the lake on Sunday afternoon, across the area along/south of I-96, as sfc troughing/convergence becomes oriented in more of a west-east fashion over srn Lwr MI. Snow showers diminishing Sunday evening behind the departing shortwave, but another brief burst in coverage/intensity possible on Monday as the final Clipper in departing northwest flow pattern aloft comes through. Highest pops Monday expected to be north of a BIV to Alma line in swly low lvl flow. -Active Weather Wed-Thur with Hydro Concerns Very little spread is shown in temperatures guidance on Wednesday so it`s now looking fairly certain that highs will reach into the mid to upper 40s. Also a strong likelihood for wind gusts of 30-40 mph out of the south-southwest as the core of a 60 kt LLJ comes overhead. Obviously this will contribute to decent snowmelt, especially south and east of GRR where the warmth hangs on the longest-- through much of Wednesday night. Ensemble support continues to grow for an inch or more of QPF from Wed afternoon into Thursday due to strong FGEN forcing within right entrance region of 180 kt upper lvl jet. Still unclear though how quick the cold air rushes in from the north and changes rain over to a mixture or snow, but it does appear likely that the area south and east of a AZO to LAN line stands a good chance of having much of the QPF fall as rain. River rises will be possible over the Kalamazoo basin and eastern reaches of the Grand as runoff from snowmelt and rainwater atop frozen ground makes it into the system. This may lead to flooding and maybe some break up ice jams, so if you live or work near rivers along and south of I-96 it is time to start thinking about a plan for monitoring the river conditions next week. Several inches of snow remains a possibility Wed night-Thursday, especially if a second wave on the front on Thursday impacts the area after the cold air arrives. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 636 PM EST Sat Feb 12 2022 Lake effect band of snow showers will lead to occasional aviation impacts through the period. IFR should be most common for KMKG tonight as those snow showers will be most focused along the lakeshore. Then for Sunday...the snow showers will build inland especially towards KAZO and KBTL as the winds become onshore. Periods of IFR look probable for those locations as well. The lake moisture and associated clouds/snow showers will continue to expand further inland. MVFR impacts are expected to prevail...but will need to monitor for possible brief IFR even for KJXN and KLAN during the day. && .MARINE... Issued at 902 PM EST Sat Feb 12 2022 The small craft advisory was allowed to expire earlier. Overall the pressure gradient weakens slightly overnight so the wind is not expected to increase. Currently all sites are below 10 knots so no headlines are anticipated at this time. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...Winter Weather Advisory until 7 PM EST Sunday for MIZ064-071. LM...None. && $$ UPDATE...MJS DISCUSSION...Meade AVIATION...MJS MARINE...MJS
Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
813 PM CST Sat Feb 12 2022 .UPDATE... Updated for evening discussion. && .DISCUSSION... No major updates needed for this evening, but will mention that our ragged band of precipitation has been persistent this evening. The combination of some mid- and upper-level lift and moistening ahead of the approaching shortwave trough has been enough to generate snow aloft all afternoon. Most has been melting and evaporating, but some brief periods of light snow with visibility down to about 2.5 miles were reported with the band as it moved through the Greenville area earlier. With temperatures falling overnight and the forcing encountering a slightly more humid air mass in the south, the HRRR has been especially persistent with depicting a second burst of activity in the Pine Belt of southeast MS late tonight and early Sunday morning. There is even support among the global guidance (GFS, ECMWF, and CMC) for some light precip as the tip of the shortwave swings through overnight. Therefore the POPs were bumped up slightly across southeastern portions of our forecast area to include a mention of "Chance" rain/snow/sleet from after Midnight tonight through around 6 a.m. The temperature profile aloft supports snow falling as long as the rates can overcome the dry sub-cloud layer. No accumulations are expected, and no impacts are expected, but a pleasant burst of flurries or light snow may surprise some in the early morning hours. Continued to trend dew points lower and winds a little higher in the wake of the front tomorrow. Exceptionally dry air in the lower levels will help surface relative humidity drop to around 20 percent or lower with daytime mixing in the post-frontal air mass. This will drive another day of "Elevated" fire weather concerns across the area. Burning should be avoided and caution exercised with any activities that create flames or sparks near vegetation. /NF/ Prior discussion below: Through Sunday: A disjointed cold front continues to gradually work its way across the region this afternoon. The theta-e gradient associated with the front this afternoon continues to lag well behind the pressure trough from just north of Alexandria to Vicksburg to the Golden Triangle. A narrow band of postfrontal showers was just entering the upper Delta and southeast AR as of 2 PM. With surface temps below 40 reaching a line from around Fountain Hill AR to Cleveland to Oxford, light snow is beginning to mix in with the rain mainly north of this line - especially in areas where temps were getting into the middle 30s and below. As this band of precip continues eastward and encounters considerable dry air it is expected to greatly diminish into this evening, though precip on the back edge of it may still briefly mix with or change over to light snow. Heading through the evening guidance has hinted at the potential for some redevelopment of light precip overnight across south MS. With low rates, above freezing air temps, and warm ground conditions, no issues are anticipated. Again, it is likely that most areas won`t see even light snow. The PoP and Wx forecast for tonight reflect only spotty, isolated precip. The greater focus for impacts in the near term is continued elevated fire danger. Even today in areas ahead of the front, RHs have fallen to near 30% in spots and with gusty northerly winds and antecedent dry conditions, we`re still seeing limited fire danger in southeast MS. For Sunday, with the reinforcing dry airmass behind the front, widespread minimum RHs in the upper teens to 20s are expected with mixing resulting in breezy conditions at times. Today`s front will provide little to no relief in the way of precipitation, and given the recent fire activity we`ve seen and expected low humidity, we have opted to increase the fire danger in the HWO/graphics to the elevated category again for tomorrow. Otherwise, weather conditions will be clear as surface ridging builds across the center of the CONUS. /DL/ Sunday night through Friday night: The primary weather concern over the forecast area going through early week will continue to be with fire danger. After a cold Sunday night, the trough responsible for the cooler weather will shift quickly east as impressive Pacific jet dynamics translate into a strong western CONUS trough. This transition will result in a warming trend with strong daytime mixing supportive of low afternoon RH and gusty surface winds. As of now, we are carrying the elevated threat for fire danger through Monday, but this could very well be extended into Tuesday given that gradient return flow winds will likely be on the increase before moisture levels can respond. Going into Wednesday, the surface wind will be stronger, but we should have steadily increasing boundary layer dewpoints by then helping to mitigate fire danger. With the approaching trough Wednesday night and Thursday, the concern quickly shifts to severe weather and perhaps even heavy rainfall for the lower MS Valley region. As described in the previous discussion, there are still some uncertain points in the global model guidance regarding the primary shortwave trough timing and strength. In the very general sense, we expect thunderstorms, and plenty of forcing and wind shear for an organized severe threat, but with model timing and wave intensity in flux, confidence is not all that high with how this is going to play out. With all that said, the broadbrushed slight severe risk denoted in the current HWO graphic for the entire area Thursday remains valid with little confidence in trying to get more specific at this point. Following the initial cold frontal passage, some guidance are hinting at maintaining a lingering baroclinic zone with subsequent shortwave energy possibly bringing an additional round of rainfall, but will continue to follow the dry/cool consensus output for now to finish the week. /EC/ && .AVIATION... 00Z TAF discussion: Northerly winds will generally continue through the forecast period at all sites, with winds turning out of the west at KGLH by 18Z Sunday. Some gusts will be possible to start, but expect winds to decrease and become less gusty by 06Z Sunday. A line of light rain or snow showers will move across the region tonight, bringing possible brief periods of reduced visibility to the MVFR range. Confidence in this decreases farther east, so has been left out of the TAFs except at KGLH and KGWO at this current time. /NF/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 26 52 29 64 / 24 0 0 0 Meridian 28 51 28 63 / 21 0 0 0 Vicksburg 27 53 30 65 / 19 0 0 0 Hattiesburg 33 54 29 64 / 28 10 0 0 Natchez 28 53 31 65 / 24 0 1 0 Greenville 26 53 29 64 / 14 0 0 0 Greenwood 24 50 28 62 / 14 0 0 0 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...None. LA...None. AR...None. && $$ NF/DL/EC
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
826 PM CST Sat Feb 12 2022 .UPDATE... Issued at 826 PM CST Sat Feb 12 2022 Couple of minor adjustments made to going forecast this evening, including raising min temps a bit across the west where cloud cover looks to be a little more prevalent than earlier, and also to slow the arrival of light snow toward morning across the far west/southwest counties slightly. Evening surface analysis depicts weak high pressure across downstate IL, with modest west-northwest low level winds across the forecast area. GOES IR satellite depicts considerable cloud cover across eastern IA and much of northern IL, which model guidance has struggled with today (especially with shallow, thin stratocu earlier). With window for clearing skies decreasing have raised min temps a bit especially across the west where temps lower than 5 above are looking less likely, in addition to increasing sky cover. Turning attention farther to the northwest this evening, a fairly vigorous mid-level short wave trough was noted in GOES vapor imagery digging south-southeast from Manitoba into the upper Midwest. Surface low pressure currently centered along the SD/NE just north of Valentine (KVTN) is progged to track southeast through the Missouri and lower Ohio valleys through Sunday, beneath the nose/left exit region of a 125 kt upper level jet streak. Low level warm advection was already noted southeast of the low across the mid-Missouri Valley in the 925-850 mb layer, which will tighten the low level baroclinic zone and is progged to result in increasing frontogenetic forcing from central/eastern IA into central IL into Sunday as the system tracks southeast. Model cross sections indicate the strongest f-gen induced ageostrophic ascent and juxtaposition with the DGZ will lay out from eastern IA into central IL - where guidance nicely depicts the QPF axis. For the WFO LOT cwa, our southwest counties will be on the northeastern periphery of this band of light snow, with some minor accums generally under an inch expected Sunday morning. Going forecast handles this placement very well, though did delay some of the higher chance pops until just after 12Z per latest model trends. Flurries will likely extend farther northeast/east across the cwa during the morning, though no accumulation is expected northeast of roughly a KVYS-KLAF line. Otherwise, no changes made to the going forecast. Updated forecast products already available. Ratzer && .SHORT TERM... Issued at 220 PM CST Sat Feb 12 2022 Through Sunday... Short term forecast interests are 1.) cloud and temperature trends this evening, and then 2.) a quick-moving clipper system on Sunday morning, bringing with it the chance of flurries areawide and potential for light accumulating snow south of a LaSalle-Peru to Watseka line. Pesky stratocumulus has stood its ground (or sky we should say) this afternoon within continued, albeit weakening, 925 mb cold air advection. Much of this is closed celled across the area as of 2 PM, pointing toward any clearing needing advection. Westerly winds around 15 kt at cloud level will help to clear some if not all of north central and far northern Illinois before mid cloud moves in late this evening, but confidence diminishes quickly for locations east of there. It`s possible any clearing is very limited from Chicago southward and especially for northwest Indiana. If that`s the case, temperatures will only drop a few degrees in total tonight. For the western CWA, where confidence is a little higher in a period of evening clearing in-sync with the surface ridge axis passage, forecast single digit lows are reasonable. MOS guidance even has lows of 5 or below for some of the sites in the west, but that seems a smidge too cold. Temperatures will probably inch up a few degrees overnight once mid cloud moves in from the northwest. The clipper system -- that is a low amplitude, progressive, wave from the northwest -- is diving southeastward into western Minnesota this afternoon. This is within the left exit region of a 125 kt equatorward pointing upper jet and a notable potential vorticity (PV) anomaly. A responsive tightening of the baroclinic zone in the 850-700 mb layer will occur to the south of the mid- level wave center and is where the best chance for a corridor of frontogenesis-forced snow is. In the past 12-18 hours, this has trended a wee bit northward in guidance solutions. This favored axis of light accumulation is still just to the southwest of the forecast area, though with the northward nudge in guidance this has resulted in an increase in the chance for snow to graze the southwest CWA. This again is mainly south of a LaSalle-Peru to Watseka line, where a 2-4 hour period of light snow may occur. The maximum lift is forecast in the -16C to -22C layer, a little colder than ideal. Envision an upper case scenario of up to an inch in places like Pontiac and Gibson City, with lowest case being no snow accumulation at all. Further to the north on Sunday morning, there is much less forcing, but with the cold air mass it should not take much lift to result in saturation of a sufficient depth for at least spotty flurries. A few guidance solutions even show splotchy QPF Sunday morning. While that looks overdone, because of the cold, can`t rule out a little bit sticking here and there. Otherwise for Sunday, the clipper passage will briefly re-enhance the low-level cold advection, and as such clouds are forecast to stick around into the afternoon. Some clearing is likely to work into the far north, but how quickly that spreads south is uncertain. Highs look to be around 20 (over 10 degrees below normal) with only a small diurnal climb. Also with the uptick in low-level cold advection, lake effect snow showers are likely to creep back up in coverage into far northwest Indiana late Sunday morning into afternoon. Forecast lake-induced equilibrium levels on the RAP and HRRR extend up to about 9,000 ft, so not shabby at all. It just looks like the window of time may be somewhat short and low-level convergence looks like it will remain over the eastern half of the lake. Plus, drier air is working in above 5,000 ft gradually through the afternoon. Some light accumulation of mainly an inch or less into Porter County in our forecast area is what we presently have forecast for this. MTF && .LONG TERM... Issued at 210 PM CST Sat Feb 12 2022 Sunday Night through Saturday... Forecast concerns include a chance of light snow early Monday morning with a weak clipper system and then a storm system for Wednesday into Thursday that will affect the region. A weak clipper system will move across the area early Monday morning bringing with it a chance for light snow or flurries. The models have always shown limited moisture with this system, which is still the case. Though there still is a chance for a dusting of snow across mainly the northern half of the area, centered in the 09z-12z time period. Added slight chance pops to the forecast for this potential but no qpf or snow for now. Confidence remains low for how much, if any, accumulation may materialize and its possible that most of what falls will be more flurries. Low temps will likely occur in the evening when some clearing is expected, then clouds will quickly increase ahead of this clipper and temps are likely to hold steady in the low teens through daybreak Monday morning. Dry weather is then expected Monday afternoon through Wednesday morning with a slow warming trend. High temps look to reach the lower 30s Monday and then possibly make a run into the lower 40s for Tuesday, perhaps holding in the 30s over the snow pack areas across the central/southern cwa. Still too early for specifics regarding the storm system for Wednesday/Thursday next week. The same concerns of the past few days remain, potential for heavy rain Wednesday evening/night, changing over to a wintry mix/freezing rain and then snow as precip ends on Thursday. Strong southerly winds on Wednesday with the potential for strong northerly winds on Thursday. The main change with the 12z operational runs is a continued jog south and perhaps an overall faster progression. The lead wave still allows for a period of moderate to perhaps heavy rain, mainly across the southern half or southern third of the area Wednesday evening. But this then pushes the cold front through faster. Even more uncertain is the second wave and how far north it moves and if it stays south of the area. A transition from rain to a wintry mix/freezing rain then snow still looks reasonable for now, for Wednesday night. And then the second wave could be quite a bit of snow, if it were to reach this far north. Still a lot of uncertainty from this distance and no changes to the blended guidance, which based on the latest model guidance has shifted considerably colder for Wednesday night into Thursday and shifted drier Thursday afternoon into Thursday evening. Still too early to include any sleet/freezing rain mention in the grids/zone forecasts, especially since it could be fairly short in duration and timing/location remain uncertain. However, from an areawide perspective, confidence is increasing enough to include limited ice mention in the HWO for freezing rain and will maintain the limited flooding mention, though as current trends show, this may be centered mainly on the southern third of the cwa. There would also be some potential for some of the rain that falls to freeze in place, limiting runoff into rivers and streams, if colder temperatures do indeed spread into the area faster. Low temps by Friday morning could be back into the low single digits, possibly low single digits below zero in the favored cold spots. Temps then moderate Friday into Saturday. cms && .AVIATION... For the 00Z TAFs... Quiet and mainly VFR conditions are expected through the TAF period. Some lingering high end MVFR cigs 2900-3000ft eventually scatter out over the next hour or two. There may even be a few snowflakes at times, but not enough for a formal TAF mention. Winds remain westerly overnight generally under 10kts then trending northwesterly during the daylight hours. Winds ease again Sunday evening becoming very light and turning west and then southwest. An area of light snow will swing across portions of Illinois Sunday AM. This is expected to remain southwest of the Chicago area terminals. It is possible it brushes RFD so have held onto a brief mention of light snow there along with any associated high end MVFR cigs. The rest of the TAF sites could see occasional non-impactful flurries during that time. Petr && .LOT WATCHES/WARNINGS/ADVISORIES... IL...None. IN...None. LM...Small Craft Advisory...IN nearshore waters until 9 PM Saturday. && $$ Visit us at Follow us on Facebook, Twitter, and YouTube at:
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
513 PM CST Sat Feb 12 2022 .UPDATE... Issued at 508 PM CST Sat Feb 12 2022 Updated for the 00z aviation discussion below. && .DISCUSSION...(This evening through Saturday) Issued at 246 PM CST Sat Feb 12 2022 Key messages: - Dangerous cold again tonight, with wind chill values between 15 and 30 degrees below zero. - Up to an inch of snow possible around the MN/WI border Sunday evening The arrival of clouds earlier than forecast has really tapped the breaks on any appreciable warmup today, with temps this afternoon struggling to sneak above zero as a result. This cloud cover is the result of WAA out ahead of a surface low over southeast MT that will quickly travel to northern Missouri tonight. Some light snow is still possible with this WAA, but we`ve been watching the HRRR slowly back away from producing much snow with this wave and there are couple of culprits. One is the forcing is quite weak given how far southwest the surface low will be from us. The other problem is when looking at forecasting soundings, we`re cold enough to where the entire atmosphere is colder than the DGZ, so you tend to get poor snow crystal generation. Have left PoPs, mostly unchanged for tonight, with a quick hit of likelies dropping through western MN, but any amounts will be under a half inch. Given how cold it stayed this afternoon and the fact that we`ll see yet another high moving in late tonight, did nudge forecast lows for tonight down some, but we could go lower, especially in central MN depending how quickly we can move clouds out of the area behind this first clipper. Did issue a wind chill advisory from western into central MN after collaboration with neighbors, as hazardous wind chills will be easy to achieve with air temperatures getting down to near -20F. Sunday will be similar to today with high pressure overhead resulting in a cold start, with a clipper bringing a chance for snow in the evening. The colder trend continues to the highs for Sunday, which now look to stay in the single digits away from the Buffalo ridge. The clipper for Sunday evening will be farther east than the one for this evening, but the surface low will be filling as it moves across MN, so a diminishing trend is expected with the band of snow that falls to the cold side of the low track. Did bump up PoPs toward the ConShort grids, to be bring in a band of categorical pops. Soundings show a warmer atmospheric profile being in place for this clipper, with large portions of the profile residing in the DGZ, so we should see more efficient snow production with this wave. With that said, moisture is very limited, so we`re talking an inch of snow at best along the MN/WI border. Behind this clipper is yet another high pressure, which means our warmup for next week gets delayed to more Monday night, with highs Monday again nudged down, with those now forecast to remain in the teens. Tuesday, a surface low will track across Canada. This will drag a cold front across our area Tuesday night. Ahead of this cold front, southeast winds will kick up for Tuesday, with highs taking a quick jump up into the upper 20s/mid 30s, with 40s possible in SW MN. Wednesday will be yet another CAA day, with highs happening in the early morning hours and temperatures slowly falling trough the day. The southern stream look to interact with the baroclinic zone with this front Wednesday into Thursday, but the resultant precipitation swath with that will remain well off to our southeast. Instead, it`s another quick blast of cold air to end the week. We continue to see a downward trend with highs for Thursday, with those looking to remain largely in the single digits once again. This cool down on Thursday will be followed by another quick warm up as yet another clipper slides off to our north Friday night. This clipper will send another strong cold front across the upper MS Valley next weekend. What`s interesting with this front though is that it will likely be running into building heights across the CONUS. This may allow the baroclinic zone with the front to get hung up over/near our area which may finally allow for some better precip chances into the our region as we get into the last week of February. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 508 PM CST Sat Feb 12 2022 Snow chances continue to look slim for this evening. Kept in some -SN BR for KAXN and KRWF, but other locales will remain dry. Some MVFR conditions are possible throughout the overnight before returning to VFR by tomorrow morning. Another clipper system will move across the region late tomorrow, bringing another chance of some light snow. This system looks a bit more promising, but the timing for most sites lies just beyond the end of the forecast period. Winds remain light throughout with a southerly shift tomorrow afternoon. KMSP...As mentioned above, went ahead an put in a PROB30 for some snow tomorrow evening after 00z. Otherwise, no additional concerns. /OUTLOOK FOR KMSP/ && .MPX WATCHES/WARNINGS/ADVISORIES... MN...Wind Chill Advisory from midnight tonight to 9 AM CST Sunday for Benton-Chippewa-Douglas-Kanabec-Lac Qui Parle-Mille Lacs- Morrison-Pope-Stearns-Stevens-Swift-Todd. WI...None. && $$ UPDATE... DISCUSSION...MPG AVIATION...Dye
Area Forecast Discussion
National Weather Service Marquette MI
701 PM EST Sat Feb 12 2022 .SHORT TERM...(Through this evening) Issued at 147 PM EST SAT FEB 12 2022 As a sfc ridge of high pressure continues to track into the region, winds will continue to decrease and back more to the west...eventually going calm by tonight. As gradient flow decreases, LES will also continue to wind down and remain closer to the shoreline into this evening. With arctic air overhead, the DGZ remains near the sfc which has led to reductions in vsbys due to smaller snowflake sizes, with amts remaining light as well. LES will continue to shift north along the wern UP through this afternoon and evening, and GOES shows this pattern well, though shouldn`t expect much more than a half an inch or so. Highs through the rest of the day will remain in the single digits across most of the UP, with some low double digits across the south-central. .LONG TERM...(Sunday night through Saturday) Issued at 321 PM EST SAT FEB 12 2022 Primary concerns tonight will be the continued very cold temperatures blanketing the U.P. and the mesolows that will develop over Lake Superior and threaten the land. Starting off this discussion with those mesolows, hi-res guidance hones in on two main lows that develop tonight: one in the east and one in the west. The one in the west is forecast to develop within LSZ-263, then riding along/near the LSZ-162 border as it approaches the shorelines of Ontonagon and Gogebic counties. The one in the east develops within LSZ-266, spinning just off/alongshore of Alger County. Earlier runs of the HRRR, such as the 15z run, showed a smaller, secondary mesolow developing within the eastern portion of LSZ-265, which seemed reasonable that a mesolow could develop along the edge of the ice there. But, later runs of the HRRR seem to be not as favored for this secondary mesolow, backing off a bit and showing that more robust one in 266. Putting all of the pieces together, the forecast for tonight into early tomorrow is some moderate snow can be expected in the west with that Ontonagon/Gogebic mesolow; moderate snow can be expected in the east with that Alger mesolow; and should a smaller, weaker mesolow develop in 265, could see some moderate snow scrapping along the Marquette County shoreline. All of these though look to keep the heavier snow offshore, but **very short- term watching is warranted should any of these rotate the heavier bands onshore.** Temperatures tonight are again expected to dip well below normal, with sub-zero temps just about everywhere. Negative teens will dominate the interior, with the mitigating factors against a wind chill advisory being the lack of meaningful winds and incoming mid-to upper-level cloud cover as an upper trough passes overhead. Which leads into the next portion of this discussion: the next synoptic disturbance will be an approaching weaker shortwave with an associated surface clipper scooting past Sunday night. Models have been cutting back on PoPs, and have this reflected in this latest forecast. There are still chances though for some snow to develop and spread across portions of the U.P. Sunday night into early Monday, but amounts, if any, will be low. Reinforcing cold air will ensure at least some LES on the backside of this grazing clipper. There looks to be a bit of a reprieve late Monday into early Tuesday for many, but then the next disturbance brings widerspread PoPs late Tuesday into Wednesday. This is associated with a low traversing across northern Ontario, allowing for some WAA to return to Upper Michigan in the middle of the week. Once this low passes though, expect the rather cold temps to return, along with accompanying LES - just in time for area outdoor winter happenings and therefore an influx of visitors. The pattern currently looks to remain chilly, progressive, and unsettled coinciding with said activities. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 700 PM EST SAT FEB 12 2022 Other than some lingering MVFR at KSAW for the next few hours, remaining TAF sites are currently at VFR levels. Nonetheless, will carry mention of light snow showers and MVFR/IFR CIGS at IWD tonight through tomorrow morning as hi-res guidance continues to pick up on a mesolow over western Lake Superior. Elsewhere, expect some fluctuation between VFR/MVFR at KCMX/KSAW. Meanwhile, winds will generally be light and variable before becoming primarily northwesterly. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 426 PM EST SAT FEB 12 2022 Outside of mesolows that develop tonight into early tomorrow, winds will generally remain less than 25 knots into early next week. Stronger winds re-emerge late Tuesday through much of the upcoming week, with gusty Srly winds looking to approach low-end gales to start, becoming Wrly on Wednesday, then Nrly on Thursday, with the winds finally subsiding a bit at the end of next week. There is a potential for some moderate to perhaps heavy freezing spray during this time period notably from late Wednesday into early Friday as a colder airmass returns behind a brief period of warmer air advecting in. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JAW LONG TERM...lg AVIATION...TDUD MARINE...lg
Area Forecast Discussion
National Weather Service Mount Holly NJ
952 PM EST Sat Feb 12 2022 .SYNOPSIS... A cold front will continue moving offshore tonight then low pressure will develop along it on Sunday and push well out to sea. Strong high pressure will build across the region through Tuesday. As the high moves offshore into Wednesday, strong southerly flow will develop through Thursday. Low pressure will pass from the Ohio Valley Thursday and progress quickly across the Saint Lawrence Valley Thursday night. This will push a strong cold front across the area Thursday night then high pressure will return for Friday and Saturday. && .NEAR TERM /THROUGH SUNDAY/... Changes with the late evening update: delayed the PoPs increasing over the near coastal areas as it appears that the precipitation shield may be a bit slower to spread eastward. This consequently resulted into a minor adjustment downward for snow amounts for portions of central Delmarva and the NJ shore. Precipitation is starting to reach the ground in the DC metro area, and the 00Z soundings around the region suggest that moisture advection is underway for the boundary layer. The 00Z soundings especially over OH and Central NY depict the upper level jet strengthening (as compared to 12 hours ago). In response, expect the surface low over eastern NC (along the cold front) to deepen and intensify over the next 12 hours. The precipitation associated with the low should spread northeastward and into our region after midnight. Boundary layer temperatures may be warm enough at the onset to result in a little rain, but the precipitation should change to a rain snow mix and then all snow before sunrise. Many of the high res models, especially the HRRR, depict the precipitation being much slower to progress eastward towards the coast overnight. I`m not ready to fully buy in to the HRRR solution, especially given that the larger scale models depict an upper level jetlet developing just SE of the main jet after 06Z. This would suggest that the precipitation would accelerate southeastward with this development. Thus, I slightly delayed the progression eastward of the PoPs, but still not nearly as slow as what the HRRR depicts. The snow is expected to be enhanced along the Interstate 95 Corridor and vicinity very late tonight by the lift under the rear entrance region of the upper level jet. This band should drift eastward on Sunday morning and off the coast during the afternoon. This will likely be another case when the Poconos, Berks County, the Lehigh Valley and northwestern New Jersey get less snow than areas to the southeast. Amounts up there should be less than 2 inches. We are anticipating 1 to 3 inches along and near the Interstate 95 Corridor. As a result, those areas are under a Winter Weather Advisory. Snowfall totals should decrease for Sussex County, Delaware and Cape May County, New Jersey due to the later arrival, slightly warmer temperatures, and a possible mix with rain at times. Around an inch or less is forecast there. While the snow is expected to end from west to east on Sunday, the sky should remain mostly cloudy for the balance of the day. Lows are forecast to range mainly from the middle 20s to the lower 30s tonight. Highs on Sunday will be considerably colder than those of today. Highs are expected to be mostly in the upper 20s to the middle 30s. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... Overall quiet but cold weather is expected through Tuesday. The trough axis responsible for the snow on Sunday will be moving offshore Sunday night. A few additional shortwaves will pass over the region into Monday through, which will bring a few periods of clouds and the potential for some flurries. Ridging will build in the wake of the trough through Tuesday. Strong cold advection will be continuing Sunday night and temperatures will fall into the 10s. This combined with sustained winds around 10 mph will result in minimum wind chills mostly in the single digits above zero (as low as -10 in the southern Poconos). The cold will continue on Monday with highs 10-15 degrees below normal and daytime wind chills mostly in the 10s. Monday night will be the coldest of the week with lows likely a few degrees lower than Sunday night thanks to improved radiational cooling conditions. The strong surface high will pass across the region on Tuesday and the airmass will begin to modify. Thus temperatures will be a bit closer to normal with highs mostly in the mid to upper 30s. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... A mid-level ridge axis will pass offshore of the East Coast early Wednesday pushing the strong and cold early week surface high pressure offshore. As a strong frontal system pushes slowly across the Great Lakes region Wednesday through Thursday, a strengthening southerly gradient flow will develop across much of the east and southeastern CONUS resulting in a rather robust warm air advection regime. This will push temperatures to well above normal levels for Wednesday and especially Thursday. High temperatures Wednesday will be in the 50s (10 degrees above normal) in most locations and in the 60s (about 20 degrees above normal) on Thursday. A few record highs could be challenged on Thursday. With lack of any moisture or forcing, Wednesday should be dry with clouds gradually increasing throughout the day and a southerly wind around 10-15 mph. On Thursday, low pressure will pass from the Ohio Valley and progress quickly across the Saint Lawrence Valley through Thursday night while intensifying. Guidance is in good agreement that the associated cold front will push across the area sometime Thursday night. This system will bring widespread rain showers and perhaps a few thunderstorms. With PWats climbing to near 1.5", heavy rain will be a threat with any convectively enhanced elements of the precipitation (or any storms). However, this system will be quite progressive and there won`t be any snowpack on the ground in most areas, so I don`t think we will see any significant or widespread flooding concerns. We`ll have to keep an eye on the potential for a marginal severe weather threat will this system as well. As it currently stands, the instability will be extremely limited, but just something to monitor in the coming days. The main timeframe of precipitation currently appears to be mostly during the Thursday afternoon and evening timeframe, but there is still plenty of time for this to wiggle around a bit. In any case, the precip should be over with the front offshore by daybreak Friday. Southerly gradient winds will increase during the daytime Thursday before the cold front arrives with sustained values of 15-25 mph and gusts of 30-40 mph possible, especially near the coasts. Breezy conditions will continue behind the front into Friday as well, but the strongest winds look to be mostly ahead of the front in the warm sector. Ridging and surface high pressure will return for Friday and Saturday with temperatures returning to seasonable values. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Tonight...VFR through 06z, then deteriorating conditions as precipitation moves into the region. Precip will likely start as rain/snow mix, particularly from the I-95 corridor east. A transition to all snow will occur for all areas by 10Z. Northwest wind 5 to 10 knots. High confidence in overall pattern, medium confidence in precipitation start time. Sunday...IFR conditions in snow in the morning, improving to MVFR in the afternoon as the snow ends from west to east. North to northwest wind 5 to 10 knots. Medium confidence. Outlook... Sunday night...Any lingering restrictions will dissipate and improve quickly to VFR overnight. Winds northerly around 5-10 kts. High confidence. Monday...VFR. Northwesterly winds 10-15 kts with some gusts to around 20 kts possible. Winds becoming westerly 5 kts or less after 00Z. High confidence. Tuesday...VFR. Westerly winds 5-10 kts during the day will shift south to southeasterly 5 kts or less after 00Z. High confidence. Wednesday through Wednesday night...VFR with increasing cloud cover. Southerly winds 10-15 kts with some gusts to around 20 kts possible. LLWS possible at night. High confidence. Thursday...Initially VFR with sub-VFR restrictions likely developing near or after 18Z. Moderate to heavy rain showers. Southerly winds 10-20 kts with gusts around 30 kts possible. Winds will shift to the northwest behind a cold front 10-15 kts with gusts up to 25 kts before daybreak Friday. LLWS possible through Thursday evening. Moderate confidence. && .MARINE... A northwest wind 10 to 15 knots is forecast to become north 15 to 20 knots for late tonight and Sunday. We are anticipating some gusts in excess of 25 knots from late tonight into Sunday morning on the coastal waters off Delaware. As a result, that area is under a Small Craft Advisory from 1:00 AM until 10:00 AM Sunday. Waves on our ocean waters should favor the 2 to 4 foot range. Waves on Delaware Bay are expected to be 2 feet or less. Outlook... Sunday night through Monday...Advisory conditions possible. North to northwesterly winds 15-20 kts. Gusts to 25 kts possible. Seas 2-4 feet. Monday night through Tuesday night...Sub-advisory conditions expected. Westerly winds 10-15 kts will shift to the southeast Tuesday night. Seas 2-3 feet. Wednesday through Wednesday night...Advisory conditions possibly developing. Southerly winds 15-20 kts with gusts up to 25 kts possible. Seas 2-4 feet, possibly near 5 feet Wednesday night. Thursday...Advisory conditions likely with gale force winds/gusts possible. Southerly winds 20-30+ kts. Seas increasing to 5-8 feet, possibly over 10 feet Thursday night. Moderate to heavy rain showers developing late. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...Winter Weather Advisory from 1 AM to 1 PM EST Sunday for PAZ070-071-101-102-104-106. NJ...Winter Weather Advisory from 1 AM to 4 PM EST Sunday for NJZ013-014-016>022-026-027. Winter Weather Advisory from 1 AM to 1 PM EST Sunday for NJZ012-015. DE...Winter Weather Advisory from 1 AM to 4 PM EST Sunday for DEZ001-002. MD...Winter Weather Advisory from 1 AM to 4 PM EST Sunday for MDZ012-015-019-020. MARINE...Small Craft Advisory from 1 AM to 10 AM EST Sunday for ANZ454- 455. && $$ Synopsis...Staarmann Near Term...Iovino/Johnson Short Term...Staarmann Long Term...Staarmann Aviation...AKL/Iovino/Staarmann Marine...Iovino/Staarmann